Early game, I rode a Rushoar and attacked ore deposits. As soon as you can, unlock the ore mining site and stick your best miners in there. If you notice at my mining camp, I have 2 ore sites, 2 coal sites, and 2 sulfur sites. these will produce more than enough of the 3. I highly recommend pals like Digtoise and Reptyro because they have level 3 mining.
